Adjustable dials have been commonly provided on pressure gauges to correct for defects in the indications of the gauge, as shown in the Annin U.S. Pat. No. 140,867, dated July 15, 1873 and in the U.S. Pat. No. 1,397,518 to hem. Other patents relate to aircraft gauges, as for example, the Fragola et al U.S. Pat. Nos. 2,700,898; Milligan 2,750,917; Davio 3,045,638; Kurowski 3,115,863 and Canning et al. 3,621,210. While these patents show pointers traversing the scale markings of the gauge or altimeter, they do not disclose the principle of visually alerting the pilot to the altitudes he has to maintain and remember to prevent flying below prescribed safe altitudes in preparation for landing.
The present invention comprises a standard altimeter having a ring adjustable about the dial of the altimeter with pointers extending inwardly therefrom, adjustable at Before Landing Check List to remind the copilot to make call-outs at, for example, 500 feet above "decision height", 200 feet above decision height, 100 feet above decision height and at decision height and alerting the pilot to apply power to level at decision height. The alerting indicator is so designed as to fit all standard altimeters used on aircraft and requires no tools to install, does not obstruct instrument readings and sets to indicate a plurality of altitude positions which may be in the order of four altitude positions, but which may vary as conditions vary.
An advantage of the present invention is that a simple addition to the altimeter of an aircraft is provided which is adjustable to alert the pilot through visual cues to the altitudes to be remembered to prevent flying below prescribed safe altitudes.
A further advantage of the invention is that the altitude alerting indicator requires no electronic assistance or audio alarms that might confuse the pilot over the many audio alarms presently used on aircraft.
A further advantage of the invention is that the alerting indicator is easy to install and adjust, requires no tools to adjust and does not obstruct instrument readings in setting to indicate a plurality of altitude indicating positions critical for landing.
A still further advantage of the invention is that the altitude alerting indicator fits all standard altimeters and thus is universally adaptable to practically all aircraft presently in use.
Other objects, features and advantages of the invention will be readily apparent from the following description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings, although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure.